#!/bin/bash

# A simple script to checkout or update a svn or git repo as source service
#  
# (C) 2010 by Adrian Schröter <adrian@suse.de>
#  
# This program is free software; you can redistribute it and/or  
# modify it under the terms of the GNU General Public License  
# as published by the Free Software Foundation; either version 2  
# of the License, or (at your option) any later version.  
# See http://www.gnu.org/licenses/gpl-2.0.html for full license text.  

# defaults
MYCOMPRESSION=""
FILES=""
SRCDIR=""

while test $# -gt 0; do
  case $1 in
    *-compression)
      MYCOMPRESSION="$2"
      shift
    ;;
    *-file)
      SRCDIR="$FILES ${2%/*}/"
      FILES="$FILES ${2##*/}"
									
      echo 'SRCDIR ' $SRCDIR
      echo 'FILES '  $FILES
      shift
    ;;
    *-outdir)
      MYOUTDIR="$2"
      shift
    ;;
    *)
      echo Unknown parameter $1.
      echo 'Usage: recompress --compression $COMPRESSION --file $FILE --outdir $OUT'
      exit 1
    ;;
  esac
  shift
done

if [ -z "$MYCOMPRESSION" ]; then
  MYCOMPRESSION="bz2"
fi
if [ -z "$FILES" ]; then
  echo "ERROR: no inputs files are given via --file parameter!"
  exit 1
fi
if [ -z "$MYOUTDIR" ]; then
  echo "ERROR: no output directory is given via --outdir parameter!"
  exit 1
fi

cd $SRCDIR
echo `pwd`
echo `ls`
echo `ls $FILES`
for i in `ls $FILES`; do
#for i in "ls $SRCIDR"; do
  FILE=`ls -1 "$i" || ls -1 "_service:*:$i"`
  #FILE=`ls -1 "$i" || ls -1 "$i"`
  if [ ! -f "$FILE" ]; then
    echo "Unknown file $i"
    exit 1
  fi
  UNCOMPRESS="cat"
  BASENAME="$FILE"
  if [ "${FILE%.gz}" != "$FILE" ]; then
    UNCOMPRESS="gunzip -c"
    BASENAME="${FILE%.gz}"
  elif [ "${FILE%.tgz}" != "$FILE" ]; then
    UNCOMPRESS="gunzip -c"
    BASENAME="${FILE%.tgz}.tar"
  elif [ "${FILE%.bz2}" != "$FILE" ]; then
    UNCOMPRESS="bunzip2 -c"
    BASENAME="${FILE%.bz2}"
  elif [ "${FILE%.xz}" != "$FILE" ]; then
    UNCOMPRESS="xz -dc"
    BASENAME="${FILE%.xz}"
  fi

  if [ "$MYCOMPRESSION" == "gz" ]; then
    COMPRESS="gzip -c -n --rsyncable -"
    NEWFILE="${BASENAME#_service:}.gz"
  elif [ "$MYCOMPRESSION" == "bz2" ]; then
    COMPRESS="bzip2 -c -"
    NEWFILE="${BASENAME#_service:}.bz2"
  elif [ "$MYCOMPRESSION" == "xz" ]; then
    COMPRESS="xz -c -"
    NEWFILE="${BASENAME#_service:}.xz"
  elif [ "$MYCOMPRESSION" == "none" ]; then
    COMPRESS="cat -"
    NEWFILE="${BASENAME#_service:}"
  else
    echo "ERROR: Unknown compression"
    exit 1
  fi

  echo "pwd: ". `pwd`;
  # do the real work
  echo "UnCompress". $UNCOMPRESS
  echo "file ". $FILE
  echo "Compress". $COMPRESS
  echo "NEWFILE ". $NEWFILE
  $UNCOMPRESS "$FILE" | $COMPRESS > "$MYOUTDIR/$NEWFILE" || exit 1

  # Check if the (compressed) target file already exists in the directory where
  # the service is invoked and drop the newly generated one. Avoids overwriting
  # otherwise identical files which only have different timestamps. Note that
  # zdiff and co all fail to do that properly...
  echo "pwd: ". `pwd`;
  if [ -f $NEWFILE ] ; then
    DIFF_TMPDIR=$(mktemp -d)
    SRC_DIR="$PWD"
    echo "SRC_DIR ". $SRC_DIR
    echo "MYOUTDIR ". $MYOUTDIR
    cd $DIFF_TMPDIR
    mkdir new old
    $(cd new ; tar -xxf "$MYOUTDIR/$NEWFILE" 2> /dev/null || mv "$MYOUTDIR/$NEWFILE" .)
    $(cd old ; tar -xxf "$SRC_DIR/$NEWFILE" 2> /dev/null || mv "$SRC_DIR/$NEWFILE" .)
    if diff -r new old > /dev/null ; then
      echo "Identical target file $NEWFILE already exists, skipping.."
      #rm -r "$MYOUTDIR/$NEWFILE"
    else
      echo "Compressed $FILE to $NEWFILE"
    fi
    cd $SRC_DIR
    rm -r $DIFF_TMPDIR
  else
    echo "Compressed $FILE to $NEWFILE"
  fi

  # we can remove service files, no need to store them twice
  rm -f "$FILE"
done

exit 0
